docs: def verifychain(self, anchors, untrusted=None):
          """
          Perform verification of certificate chains for that certificate. The
          behavior of verifychain method is mapped (and also based) on openssl
          verify userland tool (man 1 verify).
          A list of anchors is required. untrusted parameter can be provided 
          a list of untrusted certificates that can be used to reconstruct the
          chain.
  
          If you have a lot of certificates to verify against the same
          list of anchor, consider constructing this list as a cafile
          and use .verifychain_from_cafile() instead.
          """
          cafile = create_temporary_ca_file(anchors)
          if not cafile:
              return False
          untrusted_file = None
          if untrusted:
              untrusted_file = create_temporary_ca_file(untrusted) # hack
              if not untrusted_file:
                  os.unlink(cafile)
                  return False
          res = self.verifychain_from_cafile(cafile, 
                                             untrusted_file=untrusted_file)
          os.unlink(cafile)
          if untrusted_file:
              os.unlink(untrusted_file)
          return res